Regenerative turbine fuel pumps for automobiles typically operate by having a rotary pumping element, for example an impeller, fitted to a motor shaft within a pump housing. The pump housing is formed of two halves, including a pump cover and a pump bottom, which cooperate to form a pumping chamber around the outer circumference of the impeller. Vanes on an outer circumference of the impeller pump fuel as the shaft rotates and primary vortices are formed within the pumping chamber. The shape of the primary vortices, which effects pumping efficiency, is partially determined by the shape of vane grooves and partitions formed between individual vanes. Conventional electric automotive fuel pumps employ regenerative turbine impellers having vanes separated by partitions of the same height. FIG. 5 shows such an impeller 100 having vanes 102 and partitions 104 separating vane grooves 106. Partitions 104 extend so that they are flush with vanes 102. As the impeller rotates, vortices 108 rotate in pumping chamber 110 and are routed by partitions 104 toward pumping chamber top 110', and abruptly changing direction by 90.degree., resulting in pumping losses and decreased pump efficiency.